BONNEVILLE – A strong pulse of salmon continued passing over Bonneville Dam last week, prompting fishery officials to change upwards their estimates of the size of the 2006 upriver fall Chinook run.

A late-starting return caused members of the Technical Advisory Committee to downgrade the run forecast on Sept. 15, from a preseason estimate of 249,050 upriver bright fall Chinook (URB) and 51,800 Bonneville Pool Hatchery (BPH) tule Chinook to 198,700 and 36,800 adults, respectively.

But with a surge in counts at Bonneville brought the fall Chinook run past the first dam to 273,833.

Recent counts at Bonneville Dam have been “a fair amount above the 10-year average counts” for this time of the year, said the Columbia River Inter-Tribal Fish Commission biologist Stuart Ellis, who chairs TAC. This year’s run rose to a peak on Sept. 3 with a count of 14,793, dipped and then peaked again at 14,009 on Sept. 9. Daily counts fell to as low as 4,716 on Sept. 16 but rose again, averaging from 9,442 to 7,908 from Sept. 19-23. From Sept. 27 to Oct. 2, the run lost steam, dropping from 4,764 to 2,308. The count of 4,214 fall Chinook last Tuesday, Sept. 26, was more than double the 10-year average for that date.

Both Indian and non-tribal fishers appear on target to catch most of their fall Chinook allocation. A management agreement allows the non-tribal harvest of 8.25 percent of the URB run and the tribes can take 23.04 percent. The non-tribal allocation was to be split evenly between the gill-net fleet and anglers. The limits are intended to protect Snake River fall Chinook, a portion of the URB run. The Snake River Chinook are listed under the Endangered Species Act. The bulk of the URB run is unlisted, bound in large part for spawning grounds and hatcheries in the Hanford Reach.

The tribal fishers, in commercial netting and platform and subsistence fisheries, will have caught an estimated 74,300 Chinook since late August, including 40,300 URBs, as well as 17,900 steelhead.

It is expected that this week’s catch will bring that total to 82,585 Chinook (including 46,094 URBs.

“We think this will pretty much wrap it up” for the season, Ellis said of tribal commercial Chinook fishing. A very low catch, or increased run forecast, could result in the tribal fishers requesting more fishing time.

As it is, the projected catch would leave the tribes about 2,000 Chinook below their allocation.

“That I think is a pretty good buffer,” Ellis told the Compact. Fishing effort has been strong with the fish still bringing a good price from commercial buyers, he said.

The non-tribal gill-netters will have caught an estimated 25,000 Chinook by week’s end, including nearly 7,000 URBs. It is anticipated that the fleet will catch about 2,500 more Chinook in the coming weeks in fisheries primarily targeting coho salmon.

It is projected that by the end of fishing, the gill-netters will have harvested 3.7 percent of the URB run. That would bring the non-tribal total to exactly 8.25 percent. Sport fishers this late summer and early fall caught 15,715 Chinook, including 9,466 URBs for a 4.54 percent impact.

Strong steelhead dam counts have provided the impetus to slowly increase projections from the preseason forecast of 246,600 A fish (including 62,600 wild) and 50,900 B fish (including 10,300 wild). A TAC update completed early this week pegged the return at 258,400 A steelhead (65,600 wild) and 53,300 B steelhead (10,800 wild). The 2005 run included 251,600 A and 48,900 B steelhead.

The latest forecast includes a total fall Chinook return of 391,100 adult fish to the mouth of the Columbia, down from the 2005 return, 561,400, and the preseason forecast, 473,950. The total includes lower river stocks.